Answer: 160 miles
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Explanation:
x = number of miles driven, y = cost
First plan: y = 0.08x + 61.98
Second plan: y = 0.13x + 53.98
Equate the two right hand sides of each equation; solve for x
0.13x + 53.98 = 0.08x + 61.98
0.13x - 0.08x = 61.98 - 53.98
0.05x = 8
x = 8/0.05
x = 160
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Extra Info: plugging x = 160 into each equation gives us...
y = 0.08x + 61.98 = 0.08*160+61.98 = 74.78
y = 0.13x + 53.98 = 0.13*160 + 53.98 = 74.78
Therefore, driving 160 miles for each plan yields the same cost $74.78, which helps us confirm we have the right answer.
